1. Field
The present disclosure generally relates to thrust reversers for jet engines, and deals more particularly with cascade type thrust reversers, as well as a method of fabricating cascades.
2. Background
Airplanes with jet engines are often equipped with thrust reversers that increase drag on the airplane during landings, thereby reducing the speed of the aircraft. A thrust reverser increases drag by effectively reversing the flow of exhaust gases through the jet engine. In one type of thrust reverser, referred to as a cascade-type, a transcowl on the jet engine nacelle translates rearwardly to expose a cascade formed by multiple open grid panels. Closing of a blocker door causes a bypass portion of the airflow through the engine to be diverted through series of circumferentially arranged cascade vanes in the grid panels which are oriented to redirect the airflow forwardly and thereby produce reverse thrust.
The fabrication of cascade grid panels is time consuming, labor intensive and therefore expensive. Current cascade grid panels are fabricated using fiber reinforced thermoset resins which require many processing steps and specialized equipment. For example, use of thermosets require thawing of prepreg, pre-curing of strongbacks, hand layup of the individual vanes, compression molding to co-cure the strongbacks to the vanes, and post curing.
Accordingly, there is a need for a cascade for a jet engine thrust reverser that is simple in construction and is less expensive to produce. There is also a need for a low cost method of fabricating the cascade which reduces touch labor and requires fewer processing steps as well as less processing equipment.